1. Field of the Invention
The present invention relates to a wrapping-over device for a tire assembly drum, more particularly, for a solid steel tire body assembly drum, by means of which the edges of the body material projecting over the bead can be folded over the bead when the drum is expanded and then pressed in position.
2. Description of the Prior Art
The operation of wrapping over the edges of the body material is one of the most time-consuming processes in the construction of solid steel bodies. This wrapping over operation is generally carried out using special tire tools which the mechanic manually holds under the edge and by forcefully pulling upwards he gradually wraps the edge about the bead. As this edge is very resistant and tends to yield, pressure rollers can only be applied when the edge has already been largely folded over. A generally known wrapping over tool consists of a handle on which a conical finger element is rotatably mounted.
Bellows wrapping devices are also known. These are fixedly incorporated in the tire assembly drum. As the bellows are inflated they roll the edges of the body material over the bead. However, bellows wrapping systems are only suitable for tire assembly drums wherein the wrapping bellows can be located directly behind the bead mounting. Accordingly, this type of drum is either only suitable for one tire size or the bead mountings must be axially adjustable. Bellows wrapping systems also require a large amount of operating space. As the feed elements of the servicer must be brought as close as possible to the drum surface for accurate positioning of the individual layers of cord material, the servicer station must in this case always be retracted from the assembly drum in a separate operation.